Sadly the story you relate agrees, almost word for word, with the tale of woe repeated by a couple of recently retired teachers that I know.
The world has changed significantly since I left school. My view is that the present curriculum falls significantly short in attempting to modernise, to reflect those changes. I do not foresee the political will to carry out a fundamental review to make it fit for purpose. Are we trying to educate children/young adults or create pretty pictures for statisticians to place in front of endless committees so we can have an endless game of snakes and ladders playing the league tables.
When I was at school teachers taught, there were no training days, and I remember an inspector in the class once in my entire school career.
Are all the subsequent changes of benefit to the students? What is the point of a permanent inspectorate, surely rotating senior teachers in and out of the inspectorate would benefit all?